Bluetooth (SoftDevice) + high speed UART (libuarte)

[VGKilian]

Hi,

Currently I’m working on a device which is, on the one side connected to a smartphone via BLE and on the other side to another uC via UART.

Therefore, the UART speed is fixed to 1MB/s. For this reason, I must use DMA to get the UART running.

We use the nRF52840 DK.

I had a look to the example projects “ble_app_uart” and “libuarte”. Both projects fulfil our requirements to the BLE and UART connection.

Now I try to merge these projects and I’m struggling with the RTC’s.

I read that the Softdevice uses RTC0 and Timer0. Meanwhile the app_timer library is used the RTC1.

Is it true that there is no free RTC for the libuarte library?

So, I have no chance to get it running with the nRF52840?

 

Thank You,

Kilian

[Simonr]

Hi Kilian

The ble_app_uart example uses Timer1 and runs the SoftDevice which uses RTC0 and Timer0, so you're probably having trouble because the ble_app_uart and libuarte are now both trying to use Timer1.

Best regards,

Simon

[VGKilian]

Hi Simon,

i have tried Timer2 & RTC2 (NRF_LIBUARTE_ASYNC_DEFINE(libuarte, 0, 2, 2, NRF_LIBUARTE_PERIPHERAL_NOT_USED, 255, 3)) and Timer2 & Timer3 (NRF_LIBUARTE_ASYNC_DEFINE(libuarte, 0, 2, NRF_LIBUARTE_PERIPHERAL_NOT_USED,3, 255, 3);).

Both with the same result. 

I start the program with BLE running, everything works fine. If the UART communication starts the error accrues.

The pc point at nrfx_timer or nrtx_rtc.

Best regards,

Kilian

[VGKilian]

Sorry i was wrong. The pc point at 0x00014cbc or 0x000156e0. As far as i know, this should be a part of the SoftDevice.

Is there any other resource, which is used in both examples?

[Paolo D]

I'm able to reproduce this exact same SoftDevice assert, using SoftDevice S132 v7.0.1 with nRF52832. In my app I was intentionally trying to cause an assert to test my error logging function. Disabling interrupts for too long while the SoftDevice is active causes the 0x000156e0 error consistently. I used the following code:

            __disable_irq();
            nrf_delay_ms(1000);
            __enable_irq();